Snowmobiles and other vehicles used for recreational purposes such as all-terrain vehicles (ATVs), personal watercraft and the like have a throttle operator, such as a throttle pedal or a throttle lever for controlling vehicle speed and/or engine power output. The throttle lever is pivotally mounted to the handlebar so that it pivots towards and away from the handlebar in response to the driver's pushing or releasing of the throttle lever to increase or decrease speed of the vehicle. Similarly, the throttle pedal is pivotably mounted to the vehicle frame on a vehicle floor so as to be accessible by the driver's foot, the pedal being pushed towards the floor to increase the vehicle speed or engine output power. In conventional vehicles, the throttle operator is connected by a mechanical linkage to the throttle valve which regulates air flow to the engine in a fuel-injection engine or fuel intake in a carbureted engine. The degree of opening of the throttle valve directly corresponds to the position of the throttle lever. The air flow to the engine determines the power output by the engine, and therefore the performance of the vehicle. In some situations, it is desirable to control the opening of the throttle valve based not only on the position of the throttle operator but on other factors such as the current or desired engine speed (i.e. rotational speed of an output shaft of the engine), fuel economy, noise emission and the like.